0012464: iOS: You can't have a different keychain password than that of a Mac

Description

If your keychain password differs from that of your Mac, you can't sign your apps and in the end can't build.

Keychain and Mac passwords are 2 different things independent of each other. There should be another field asking user for their keychain password with an option to leave it blank, which by doing so would cause GM:S to default to user password.

Steps To Reproduce

- Open Keychain Access
- From the menu choose "Change keychain password"
- Try building for iOS from GM:S